The present invention relates to a positioning device for positioning a patient in relation to a medical examination or therapy device. The device is configured for multiple use by a plurality of patients and comprises means for indicating the position of an anatomical area of one of the patients in relation to the positioning device and means for the reproducible positioning of the patient in relation to an examination or therapy area of the medical examination or therapy device.
The positioning of a patient to be examined or treated correctively in relation to an examination or therapy device is essential for the effectiveness of a treatment. The positioning requires a correspondingly high level of accuracy. When carrying out complex treatments, for which examination and therapy devices are deployed in an alternating manner, reproducible positioning of the patient is of crucial importance. One example of such a complex treatment is radiotherapy, in which, on the one hand, examinations are carried out using medical imaging devices for diagnosis purposes and, on the other hand, therapy takes place with radiotherapy devices. Generally the success of the treatment is finally monitored again using a medical imaging device, for example a magnetic resonance device, which is known as a MR device, or a computer tomography device, which is known as a CT device.
With such complex treatments, information obtained during the examination, such as the position of a tumor in the body, is required for therapy, in order, for example, to draw up a radiation plan. To allow the transfer of such information from the examination device to the therapy device, markings are generally painted on the body of the patient and located in relation to the different examination or therapy devices. Such markings can be lost over time, for example if the patient is cleaned with alcohol. But in the case of radiotherapy, radiation treatment is divided into a plurality of radiation sessions. For example, between 20 and 30 sessions are normally required for prostate radiation. In addition, several control examinations are carried out, for example, using CT or MR devices. The tumor radiation is closely followed by a number of examinations to monitor the success of the radiation. The patient has to be repositioned for each of these examinations or radiation sessions. This is very time-intensive and there is a risk of incorrect positioning. Poor positioning results in an avoidable, additional radiation load due to inaccurate radiation and additional CT control examinations.
Alternatives to the above-mentioned painting of markings on the patient are, for example, fitted devices produced individually for each patient and requiring a great deal of time and effort or plaster casts for children. For example, DE 33 40 482 C2 discloses a device for producing a transparent and radiation-permeable mask for applying the marking required for the accurate radiation of human body parts. The individually tailored, patient-specific mask is positioned and fixed in the correct place on the patient. Characteristic lines are used to identify both the place at which radiotherapy is to be carried out and also the three-dimensional position of the body part in relation to the device.
Additional devices are, for example, known from U.S. Pat. No. 5,370,117 and U.S. Pat. No. 5,702,406, which claims priority from DE 44 32 891 A1. For example, U.S. Pat. No. 5,702,406 discloses a device for non-invasive steriotactic immobilization in a reproducible position. It comprises a mask made of a number of elements, which is tailored individually to the anatomical contours of a patient and is connected via a connecting device to a reference system, in particular a head ring.
The use of markers is known from DE 199 08 903 C2, WO 02/32328 A2 and US 2003/0137510 A1, which claims priority from DE 10025 922 A1 and the use of a template from U.S. Pat. No. 5,911,126, which claims priority from EP 0 760 622 B1.
A system for automatic identification of the shape of a patient and for instrument position determination is known from US 2002/0087101 A1. The external shape of a patient is thereby determined using a first set of curve sensors and aligned with volumetric image data from CT or MR devices. The position of an instrument is established using a second set of curve sensors in relation to the first set and, therefore, in relation to the image data set.
A device for functional electrical stimulation of a body part is known from US 2003/0114893 A1. Accurate, simple and repeatable positioning of the device in relation to activation points of muscles of the body part is achieved using a location system, which comprises both means for allowing rotation-related location and also means which allow longitudinal location of the device.
A device for aligning the hip, e.g. during sleep, is known from U.S. Pat. No. 5,123,407.